Let's see who gets this one

2000 Chevy venture van (automatic) with 190,000 miles on engine. “Clunking” noise when accelerating/decelerating as engine/tranny passes up or down through the gears. Also, a “whining” noise can be heard when accelerating, either in gear or in neutral. Rarely happens in cold weather until van has been running for quite a while. Happens regularly in warm weather. If I shut the engine off and wait 10-15 seconds before restart, it usually goes away, but will return indiscriminantly. Tranny was completely rebuilt last year but it still occurs.

Neither the tranny shop nor the Chevy dealer can figure it out.

My first suspect would be a bad u-joint on the drive shaft.
Has this area been checked?

However, if this van is FWD, then my theory is bogus.
Is this van FWD or RWD or AWD?

This van is FWD.

Well, then you can forget my theory.

Next!

Thanx anyway!

Okay, my new theory, subject to being refuted by someone really knowledgeable about transmissions, is that you have a bad thrust bearing in the transmission.
(Please note that I am fully prepared for this new theory to be bogus!)

Transman, are you here to lend your expertise?

The shop which needs to look at it is an alignment (suspension) shop to look for the source of the “clunking”

Should that have been replaced when I had the tranny rebuilt?

How would bad alignment or bad front end components cause a whining noise upon acceleration?

Of course, the whining noise could be totally unrelated, especially since the OP states that he/she hears that noise when accelerating “either in gear or in neutral”. I’m not sure how you can accelerate while in neutral, but…

How about engine and trans mounts. You did not mention that at least the trans mount had been replaced when overhauled. Just another theory.

Could the “whinning” be the alternator by chance?

thanx for the input VDC. to clarify, the “whining” noise occurs whenever I step on the accelerator. If there is no whining noise, then the “clunk” does not occur while passing up or down through gears, so i assumed it is related.

Not sure if the mounts were replaced when the tranny was overhauled. I will check my invoice.

The tranny is a 4T65E.

A faulty pressure control solenoid in the tranny can cause a harsh shift. More commonly referred to as a ‘clunk’ when shifting.

Sometimes an extra change of tranny fluid and filter (to remove foreign matter) will help.

You said the tranny was rebuilt last year…but…who knows?

At any rate, transman can give you a proper answer, however, be prepared to supply more info.

Could the torque converter “whine” and clunk if not going in and out of lock up correctly?

THANX,
HOW DO I GET IN TOUCH WITH TRANSMAN?

He is a forum member, and he does check in fairly often. Just be patient for a couple of days, and hopefully he will see your post.

I don’t usually recommend a new thread, but in this case, perhaps a better title would be something like “2000 Chevy Venture Trans Problems”.

thnx. I will change the title and see what happens.

Maybe 190,000 miles is all you get…Or live with it. Or save America and buy a new vehicle. We get tired of playing “Stump The Chump”.

Personally, my many years of experience tells me automatic transmissions are the limiting factor in the life of FWD vehicles. Your problems support my position. Others will disagree. Nothing lasts forever. The life of the FWD transmission is typically much less than that. Rebuilding them is a crap shoot. You win some, you lose some.

Yep, love those positive responses.
Thanx for the input…

No idea from my vantage point but has this vehicle actually been scanned for any transmission codes?
When the trans was rebuilt was the converter also replaced?

To go hand in hand with another post about “rebuilt engines” there is only one correct method of rebuilding either a transmission or an engine. There are numerous other no so proper methods.

Some transmission places may consider a rebuild as nothing more than a set of clutches, seals, and gaskets. This is called a “soft” rebuild and some of these can be on somewhat shaky ground. A “hard” rebuild is a proper one in my opinion, if done by a pro. This means the above plus bushings, bearings, new converter, updates, yada, yada, yada.

On the offchance the clunking and whirring could be unrelated, you might check the engine/transmission mounts for the clunking and inspect things on the front of the engine in regards to the whirring; idler/tensioner bearings, alternator bearings, etc.